I don't hear any 'scream' after the shot, but I'm not working off a great audio set up at the moment.
Screaming after the shot would make George's claim more credible to me, since it would show he was still fearful (he says he didn't know that his shot had hit Martin at first) - since Martin can't be screaming if he apparently only said 'you got me' or something.
Thanks for letting me know you don't hear a scream.
Re it making GZs claim more credible: I understand what you're saying but if so, I think he would've been certain to mention it. From what we can tell, he hasn't mentioned it at all, only the "You got me", etc., lines and his not knowing he'd shot TM, etc., as his (GZs) account of what happened.
One might also be able to view it from the TM side, i.e., it could also be (just assuming it is a scream; I would guess at this point it isn't but just assuming it is
), a last ditch effort of someone who has just been shot, trying to get out one more scream for help and not being able to do so, type of thing.
No matter what, whether the sound turns out to be human/ non-human, it just seems given it's proximity to the actual shot, that someone would've looked into what exactly was the source of that sound.